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[PEM16-33] Hectometric Line Radiation found by the Arase (ERG) satellite
Keywords:Arase, Hectometric radiation
We reports newly observed line radiations with even higher frequencies in hectometric wavelengths of 600 to 1,700 kHz found by the Arase (ERG) satellite. Since they are composed of line spectra, we have named this as ‘hectometric line radiation’ (HLR). Although they look like extension of kilometric continuum, they are generally line emissions with long durations different from KC. This has the following characteristics.
1. This is composed of line emissions.
2. This sometimes continues more than five hours.
3. Their frequencies occasionally change.
4. The frequency rage is from 600 kHz to 1,700 kHz.
5. This terminates before the local plasma frequencies or UHR frequencies become close to the frequencies of emission lines.
6. It is not possible for medium frequency broadcasting signals to pass the ionosphere since foF2s are higher the signal frequencies.
In conclusion, the HLR is believed to be new radio emissions generated in the topside ionosphere.
Gurnett, D. A. (1975), The Earth as a radio source: The nonthermal continuum, J. Geophys. Res., 80, 2751-2763.
Gurnett, D. A., and R. R. Shaw (1973), Electromagnetic radiation trapped in the magnetosphere above the plasma frequency, J. Geophys. Res., 78, 8136-8149.
Hashimoto, K., W. Calvert, and H. Matsumoto (1999), Kilometric continuum detected by Geotail, J. Geophys. Res., 104, 28,645? 28,656.
Hashimoto, K., J. L. Green, R. R. Anderson, and H. Matsumoto (2006), Review of kilometric continuum, in geospace, Electromagnetic Waves and Radiation, Lect. Not. in Phys., vol. 687, edited by J. W. LaBelle and R. A. Treumann, pp. 37?54, Springer, New York.